Matter apps

A Matter app is a tool built on a space’s tables. It has pages in Matter, and some apps also have background work on your computer and routines that agents run for them. The app’s records are the space’s own, so you see the same data in the app and in Matter.

To build one, see What a Matter app is.

Open an app

In the sidebar, each space lists its apps under an Apps heading, after its other items. Click an app to open its first page. An app with several pages expands to list them. Pages limited to other roles in the workspace aren’t listed.

The app’s header shows the page you’re on and a menu button with the app’s actions.

Pins and badges

To keep an app or a page in the sidebar’s Pinned section, right-click it and choose Pin. In an open app, the menu can also pin just the page you’re on. Unpin removes a pin.

A page can show a badge: a live count beside its name in the sidebar, such as how many items wait for you. A collapsed app shows the total of its pages’ counts.

Trust an app

An app acts as you: it can read and change the tables of its space and start chats with your agents, and some run their own code on your computer. So the first time you open an app from someone, Matter asks whether you trust them. For an app Sam publishes (every version is signed with its publisher’s key), the prompt reads Trust apps from Sam?

• Trust opens the app. Every app Sam publishes, and every new version of them, then opens without asking, whoever on Sam’s team deployed it.
• If you opened it by mistake, just go somewhere else, or choose Go back. The app stays closed, and the question waits on its page.

Apps you publish yourself don’t ask. To stop trusting someone, choose Stop trusting, followed by their name, from the menu of any of their apps. See Trust and security.

While an app runs

Opening an app with background work starts it on your computer. It keeps running, even after Matter restarts, until you choose Stop from the app’s menu. A green dot beside the app in the sidebar means it’s running on this computer. The Matter icon in the menu bar also lists running apps, each with Open and Stop.

An app can send you notifications, at most 10 an hour. Clicking one opens the app.

Set up an app

Some apps have routines that run for each member. These show Set up in their header until you set them up.

1. Click Set up.
2. Choose which of your computers runs the app’s routines. They run as you.
3. Click Set up. If the app has its own setup page, it opens next to ask what its routines need.

The routines then join your routines. Their results show on the app’s pages, so they only add to your brief what needs you, such as a problem or a decision. In the app’s menu, Move setup to this computer moves them to the computer you’re using, and Turn off for me removes them.

Versions

Each deploy makes a new version. Choose Versions from the app’s menu to see them, with who deployed each. The one everyone uses is marked Current.

• Preview opens a version for you alone. Its header shows Preview, and it stops when you close it.
• Make current makes a version the one everyone uses: a rollback, or a preview going live.

If a new version becomes current while the app is open, its header shows New version. Click it to reload.

Matter keeps an app’s current version, the 20 before it, and anything from the last 30 days. Older versions, and previews more than 30 days old, are deleted.

Matter version requirements

An app can require a range of Matter versions. On a computer outside that range, the app doesn’t open. It shows “Update Matter to use Prospector” when Matter is too old, or says the app doesn’t run on this version of Matter yet when Matter is too new. See Matter versions.

The Dev pill

While a developer runs matter app dev, the app’s header on their computer shows Dev and their dev server’s address, and its pages come from that server. Everyone else keeps using the current version.

Manage a space’s apps

Open the space’s settings (the gear beside its name in the sidebar) and choose Apps, or choose Manage apps from an app’s menu. Each app shows its version and which computer runs its app routines. Its menu has:

• Rename: change its name or its emoji icon.
• Move to space: its tables stay behind, so move them too or the app won’t find them.
• Run app routines on this computer: some routines run once for the whole app rather than per member. They run on one member’s computer, as that member. This moves them to you, on this computer.
• Archive: the app leaves the sidebar and stops on every computer, and its routines wait until you Unarchive it.
• Delete: deletes the app, its versions and its routines for everyone. Its tables stay in the space. This can’t be undone.

To create an app, click New app there, or the + beside the sidebar’s Apps heading, which appears once a space has an app. Give it a name and an icon, and click Create app. Its app routines run on your computer until someone moves them. It stays empty until someone deploys to it (see Developing and shipping), or you ask Matter to build it.

Guests can open apps and preview versions, but can’t create, change or delete them.